在告警模块上操作，调整关键的系统电压包括（）。
参考答案：电池电压、均衡电压、负载脱离电压、电池电压过高电压和电池电压欠压电压
有一框苹果58个，送给大班小朋友15个，送给小班小朋友20个，还剩多少个？
— How long do you think it is?
— It is ________ two metres. I can touch its top. [ ]
A. at least
B. at present
C. at most
D. at an end
